Use kref for reference counter of bio.
This patch also removes BUG_ON() for freeing unreferenced bio.
But kref can detect it if CONFIG_DEBUG_SLAB is enabled.
Signed-off-by: Akinobu Mita <[email protected]>
CC: Jens Axboe <[email protected]>
CC: Greg KH <[email protected]>
Documentation/block/biodoc.txt | 2 +-
fs/bio.c | 17 ++++++++++-------
fs/xfs/linux-2.6/xfs_aops.c | 1 -
include/linux/bio.h | 4 ++--
4 files changed, 13 insertions(+), 11 deletions(-)
Index: 2.6-git/Documentation/block/biodoc.txt
===================================================================
--- 2.6-git.orig/Documentation/block/biodoc.txt
+++ 2.6-git/Documentation/block/biodoc.txt
@@ -462,7 +462,7 @@ struct bio {
used as index into pool */
struct bio_vec *bi_io_vec; /* the actual vec list */
bio_end_io_t *bi_end_io; /* bi_end_io (bio) */
- atomic_t bi_cnt; /* pin count: free when it hits zero */
+ struct kref bi_kref; /* pin count */
void *bi_private;
bio_destructor_t *bi_destructor; /* bi_destructor (bio) */
};
Index: 2.6-git/fs/bio.c
===================================================================
--- 2.6-git.orig/fs/bio.c
+++ 2.6-git/fs/bio.c
@@ -139,7 +139,7 @@ void bio_init(struct bio *bio)
bio->bi_size = 0;
bio->bi_max_vecs = 0;
bio->bi_end_io = NULL;
- atomic_set(&bio->bi_cnt, 1);
+ kref_init(&bio->bi_kref);
bio->bi_private = NULL;
}
@@ -208,6 +208,14 @@ void zero_fill_bio(struct bio *bio)
}
EXPORT_SYMBOL(zero_fill_bio);
+static void release_bio(struct kref *kref)
+{
+ struct bio *bio = container_of(kref, struct bio, bi_kref);
+
+ bio->bi_next = NULL;
+ bio->bi_destructor(bio);
+}
+
/**
* bio_put - release a reference to a bio
* @bio: bio to release reference to
@@ -218,15 +226,10 @@ EXPORT_SYMBOL(zero_fill_bio);
**/
void bio_put(struct bio *bio)
{
- BIO_BUG_ON(!atomic_read(&bio->bi_cnt));
-
/*
* last put frees it
*/
- if (atomic_dec_and_test(&bio->bi_cnt)) {
- bio->bi_next = NULL;
- bio->bi_destructor(bio);
- }
+ kref_put(&bio->bi_kref, release_bio);
}
inline int bio_phys_segments(request_queue_t *q, struct bio *bio)
Index: 2.6-git/fs/xfs/linux-2.6/xfs_aops.c
===================================================================
--- 2.6-git.orig/fs/xfs/linux-2.6/xfs_aops.c
+++ 2.6-git/fs/xfs/linux-2.6/xfs_aops.c
@@ -272,7 +272,6 @@ xfs_end_bio(
return 1;
ASSERT(ioend);
- ASSERT(atomic_read(&bio->bi_cnt) >= 1);
/* Toss bio and pass work off to an xfsdatad thread */
if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
Index: 2.6-git/include/linux/bio.h
===================================================================
--- 2.6-git.orig/include/linux/bio.h
+++ 2.6-git/include/linux/bio.h
@@ -106,7 +106,7 @@ struct bio {
struct bio_vec *bi_io_vec; /* the actual vec list */
bio_end_io_t *bi_end_io;
- atomic_t bi_cnt; /* pin count */
+ struct kref bi_kref; /* pin count */
void *bi_private;
@@ -249,7 +249,7 @@ struct bio {
* returns. and then bio would be freed memory when if (bio->bi_flags ...)
* runs
*/
-#define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
+#define bio_get(bio) kref_get(&(bio)->bi_kref)
/*
--
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
